Vinyl chloride polymers stabilized with metal salts of carboxylic acids mixed with organic titanates



VINYL CHLORIDE POLYMERS STABILIZED WITH METAL SALTS F CARBOXYLIC ACIDSMIXED WITH ORGANIC TITANATES Harold M. Olson, Vermilion, Ohio,

shaw Chemical Company, ration of Ohio No Drawing. Application June 30,1953, Serial No. 365,228

2 Claims. (Cl. 260 -23) assiguor to The Har- Clevelanti, Qhio, a corpo-This invention relates to improved plastic compositions and morespecifically to stabilization of vinyl chloride plastics.

In the manufacture of plastics containing vinyl chloride resins andplastics containing vinyl chloride along with other vinyl compounds suchas vinyl acetate, there are usually incorporated plasticizers, metallicstabilizing compounds dispersed in the composition and additionalcompounds suitable for further improving the stability of the resin inthe plastic against the action of aging and of heat and/or light.Numerous compounds have been used for these latter purposes, such assubstituted phenols, esters of salicylic and stearic acids, and organicphosphates and phosphites, to mention only a few which have proved moreor less useful.

In the compounding of resins of the type indicated, it 0 is customary tomake use of suitable plasticizers, such, for example, as high boilingesters, e. g., dioctyl phthalate, phosphates, polymeric compounds, etc.as well as secondary plasticizers, such as chlorinated paratfins, etc.;metal soaps, such as for example, zinc and/or cadmium and/ or bariumstearates, ethyl hexoates, ricinoleates, and the like, and othercarboxylic acids having from 8 to 18 carbon atoms; stabilizer assistantssuch as alkyl and aryl phosphites, epoxy compounds, etc.; these andsimilar materials which may be chosen being dispersed in the vinylchloride polymer by suitable mixing at an elevated temperature and beingeffective to stabilize more or less against degradation resulting fromaging or exposure to heat or light.

It has now been discovered in accordance with the present invention thatimproved clarity, usually accompanied by stability above that resultingfrom use of the metal stabilizers alone can be obtained by the usetherein of titanium organic compounds of the form where W and X areselected from the class consisting of radicals of the form R0 where R isselected from the class consisting of alkyl radicals having from 3 to 18carbon atoms and hydroxyl and amine substitution products thereof, and Yand Z are selected from the class consisting of radicals of the form R'Owhere R is selected from the class consisting of alkyl radicals havingfrom 1 to 18 carbon atoms and hydroxyl and amine substitution productsthereof, hydroxyl, and radicals of the form R"CO2, where R" is selectedfrom the class consisting of alkyl radicals having from 1 to 18 carbonatoms and hydroxyl and amine substitution products thereof.

More restricted groups of additives according to the invention aremonomers and polymers of the following formulae:

Ti R0 \O R 2,777,826 Patented Jan. 15, 1957 which for convenience may bewritten R4O4Ti, where R represents an alkyl group having from 3 to 18carbon atoms, the four such alkyl groups being not necessarily the same.

ice

RO\ /0Y A YO OR which for convenience may be written R303TiO2CR', whereR represents hydrogen or an alkyl radical having from 1 to 18 carbonatoms and 02CR' represents a fatty acid radical having from 8 to 18carbon atoms. Specific examples of such compounds are found in the tablebelow wherein specific compositions of stabilized plastics according tothe invention are set forth.

By the term vinyl chloride resin is understood not only the vinylchloride polymer itself but also copolymers of vinyl chloride with vinylacetate, vinylidine chloride, styrene, and the like wherein vinylchloride constitutes the major portion of the resin exclusive ofplasticizer (if any), stabilizer, and pigment and filler components, ifany. The novel auxiliary stabilizers or anti-clouding agents or clarityproducing means are used in combination with metallic compounds such aszinc, tin, barium or cadmium organic compounds, suitably mixtures ofbarium and cadmium compounds such as the ethyl hexoates, stearates, orthe like, with or without epoxy compounds, and may be used in connectionwith organic phosphites and other known anti-clouding agents.

In preparing the novel compositions according to one present specificpractice of the invention, the vinyl resin, plasticizer, metal soap typeof stabilizer or stabilizers, the auxiliary stabilizer or clarityproducing additive according to the present invention and any pigmentsor diluents such as inert-fillers are thoroughly premixed. The mixturemay then be transferred to a roll mill where it is further mixed to thedesired extent after which it may be formed into any desired shape inaccordance with customary practice.

In order to test the product under conditions more severe than arenormally encountered in practice, samples thereof were heated to atemperature higher than the temperature normally employed in manufactureof articles 0 of commerce and for times longer than ordinarilyexperienced. The examples below were tested at C. which is rathercritical temperature for this type of compound in that at a few degreeshigher, most of the samples would fail, whereas at several degreeslower, they would 5 mostly show up well.

The manner in which the auxiliary stabilizers perform their function isnot fully understood but it is believed that it is by formation ofcompatible complexes with the metallic chlorides formed by the reactionbetween hydrogen chloride and the metallic soaps or the like.

The dioctyl phthalate is merely one example of plasticizer and themixture of barium and cadmium soaps is merely one example of metallicstabilizer suitable for use in the practice of the invention. Otherconventional plasticizers and other metal-organic compounds may be usedor the plasticizer may be omitted altogether depending upon the intendeduse. Examples of other plasticizers are: tricresyl phosphate,dibutylsebacate, and the like. Barium, cadmium, zinc, calcium and tincompounds, each may be used alone as the metallic stabilizer, forexample barium stearate, barium ethylhexoate, barium ricinoleate and thecorresponding cadmium, soaps may be used as well as other barium andcadmium organic compounds, tin, calcium and zinc organic compoundscorresponding and the like.

The metal stabilizers such as barium stearate or cadmium ethyl hexoatemay be used in proportion up to 10 parts by weight for each hundredparts by weight of vinyl chloride polymer but preferably are used inproportion from 0.1 to parts per 100 parts vinyl chloride polymer, andthe auxiliary stabilizer may be utilized in like proportion. From 0.1%to 10.0% by weight total metal stabilizer and from 0.2% to 5% by weightof anticloud agent may be considered optimum.

In the case of the examples below, improved clarity,

that is, anti-clouding is characteristic. The products are mostlycolorless or water-white. In the case of Example 4, the finalcomposition was of a transparent brown color of improved clarity. Testson these compositions omitting the novel anti-clouding agent or clarityproducing means showed definite clouding.

Specific examples are as follows:

Having thus described the invention, what is claimed 1. A stabilizedresin of improved clarity, being a resin of the class consisting ofpolyvinyl chloride and copolymers of vinyl chloride withmono-ethylenically unsaturated compounds copolymerizable therewith inwhich vinyl chloride is the major constituent, said resin beingstabilized by the use of a metallic stabilizer of the class consistingof cadmium, barium, calcium, zinc, and tin compounds of aliphaticcarboxylic acids having from 3 to 18 carbon atoms in proportion from0.1% to 10% based upon the weight of resin and cooperating meansincorporated in said resin for producing improved clarity, said meanscomprising a tetra alkyl titanate wherein each alkyl group contains from3 to 18 carbon atoms incorporated therein in proportion from 0.2% to 10%based upon the weight of the resin.

2. A stabilized resin of improved clarity, being a resin of the classconsisting of polyvinyl chloride and copolymers of vinyl chloride withmono-ethylenically unsaturated compounds copolymerizable therewith inwhich vinyl chloride is the major constituent, said resin beingstabilized by the use of a metallic stabilizer of the'class consistingof cadmium, barium, calcium, zinc, and tin compounds of aliphaticcarboxylic acids having from 3 to 18 carbon atoms in proportion from0.1% to 10% based upon the weight of resin and an agent in saidresiu forproducing improved clarity, said agent being tetra 2-ethylhexyltitan-ate incorporated therein in proportion from 0.2% to 10% based uponthe weight of the resin.

Polyvinyl chloride resin Dioc-tyl nhthalate Tricregyl phn nhafn Cadmiumlaurate Barium steer-ate.-- Calcium stearate Zinc stearate. Cadmiumethylhexoate Starmous ethylhexoate Barium lam-ate Tetra n butyl titanateHydrcxy titanium stearate.-.

Bydroxy titanium cocanut acyla Hydroxy titanium castor aeylate Trie thanolamine titanate N linseed acid Triethanolamine titanate N stearateoctyleueglyeol titan 21in References Cited in the file of this patentUNITED STATES PATENTS Boyd Dec. 18, 1951 OTHER REFERENCES Article byTally et aL: Modern Plastics, vol. 27, No. 4, December 1949, pages111-116.

1. A STABILIZED RESIN OF IMPROVED CLARITY, BEING A RESIN OF THE CLASSCONSISTING OF POLYVINYL CHLORIDE AND COPOLYMERS OF VINYL CHLORIDE WITHMONO-ETHYLENICALLY UNSATURATED COMPOUNDS COPOLYMERIZABLE THEREWITH INWHICH VINYL CHLORIDE IS THE MAJOR CONSTITUENT, SAID RESIN BEINGSTABILIZED BY THE USE OF A METALLIC STABILIZER OF THE CLASS CONSISTINGOF CADMIUM, BARIUM, CALCIUM, ZINC, AND TIN COMPOUNDS OF ALIPHATICCARBOXYLIC ACIDS HAVING FROM 3 TO 18 CARBON ATOMS IN PROPORTION FROM0.1% TO 10% BASED UPON THE WEIGHT OF RESIN AND COOPERATING MEANSINCORPORATED IN SAID RESIN FOR PRODUCING IMPROVED CLARITY, SAID MEANSCOMPRISING A TETRA ALKYL TITANATE WHEREIN EACH ALKYL GROUP CONTAINS FROM3 TO 18 CARBON ATOMS INCORPORATED THEREIN IN PROPORTION FROM 0.2% TO 10%BASED UPON THE WEIGHT OF THE RESIN.